Patent GB-928855-A (GB)
Title: Coin operated means incorporating credit storage
Inventor: BURNS DAVID HENRY
IPC: H04N7/16
Filed: 1959-09-07
Abstract: 928,855. Coin-freed television apparatus. BRITISH TELEMETER HOME VIEWING Ltd. Sept. 7, 1959, No. 30474/59. Class 27. The receiving apparatus of a subscriptiontelevision system employs coin-operated mechanism having a demand dial 48 set by pulses from the transmitting station for showing the required price for a programme, a credit dial 34 for showing the amount of over-payment when coins in excess of the required price are inserted and means for applying this credit to the reduction of the price required for a subsequent programme. As shown in Figs. 1 and 2, the demand apparatus 58 operated by pulses from the station and the coin receiver 62 both rotate a shaft 20 in the counterclockwise direction. The shaft 20 has a spider or crank 22 carrying a planet gear 24 which meshes with a sun gear 26 on a shaft 28 and with an internal gear 54 on the demand dial 48. The credit dial 34 and a ratchet wheel 38 engaged by a pawl 42 are also carried by the shaft 28, which is biased towards clockwise rotation by a spring 40 or a torque motor. In the zero position shown in Fig. 2, a stop 56 engages the left-hand side of a stop 52 and a blank space on the dial 48 appears under a window 60. When a programme which is scrambled until paid for is about to be transmitted, pulses sent to the demand apparatus 58 rotate the shaft 20 counterclockwise and the planet gear 24 travels round the sun gear 26, which, with the shaft 28, is prevented from rotating to the spring 40. The planet gear thus rotates the demand dial 48 counterclockwise and winds up a spring 61 until the required price is shown under the window 60; the price indications on the dial increase counterclockwise so that the , smaller the counterclockwise movement the greater the price required. When coins totalling the price required are inserted, the receiver 62 rotates the shaft 20 further counterclockwise and the demand dial 48 is moved until the stop 56 engages the stop 52 on the right-hand side and PAID appears under the window 60. The contact of the stops 52, 56 causes a decoder to be coupled to the receiver and the programme is unscrambled. If coins in excess of the required price are inserted, the crank 22 continues to rotate after the stops 52, 56 have engaged and the gear 24, since the demand dial is now stationary, rotates clockwise and causes the gear 26 and ratchet wheel 38 to rotate counterclockwise against the action of the spring 40 and moves a stop 63 on the credit dial away from a stationary pointer stop 36. The credit established may be realized by releasing a pawl 42 from the ratchet wheel 38 by means of a solenoid 44 or other means actuated either on insertion of another coin or, at the discretion of the user, by a push-button. On release of the pawl, the gear 26 rotates clockwise to cause counterclockwise rotation of the gear 24 and thus of the demand dial 48 so that the effect is the same as inserting coins. At the end of a paid programme, a solenoid 59 is energized in response to a pulse from the transmitting station or by switching of the set and a pawl 57 is withdrawn from teeth 55 so that the spring 61 can rotate the dial back to initial position with the stop 56 engaging the lefthand side of the stop 52; the shaft 20. must be uncoupled from the demand apparatus 58 and the coin receives 62 to allow free rotation of the gear 24. The linear differential shown in Fig. 3 comprises a beam 71 with a coin member 70 pivoted at the upper end and a demand member 72 pivoted at the middle. At the lower end, ratchet teeth 78 engage a pawl 80. With zero credit and zero debt, the lip 74 engages a stop 76 and the pawl 80 engages the tooth on the extreme right and establishment of debt causes movement of the beam 71 about the pawl 80 as a fulcrum to the right, the lip 74 moving away from the stop 76. Insertion of coins will cause the upper member 70 to return the middle member 7.2 until the stop 76 is engaged and continued insertion will cause the beam to-rotate about the middle pivot and move the ratchet teeth over the pawl to establish credit, the spring 82 thus being compressed. For using some or all of the credit to satisfy a subsequent debt, the pawl 80 can be withdrawn from the ratchet teeth by operating a solenoid 84.